Motography (Apr-Dec 1911)

May, 1911. MOTOGRAPHY 75 lamps. The latest types of lamps have an extension on the carbon arms to which the leads may be attached. If it is necessary to attach the leads directly to the carbon arms, terminals or lugs of some form should be used. These terminals are made of copper, but the use of solder should be avoided as it melts under the intense heat of the arc. If the carbon holders have no extension a piece of copper or wire about three inches long should be fastened to the binding post of the lamp, and the other attached to the lead wire. In this way the ends of the wires are removed from the heat. In regard to the adjusting handles, every lamp should have at least three : One to feed the carbons together, another to tilt the lamps up or down, and a third to push the whole lamp back and forth. A screw with a very large thread should be used in this last case so that the lamp can be moved quickly. Some lamps have an adjusting handle by which the lamp may be moved sideways and others have arrangements to feed each carbon separately. The lamp-house should be large and have a door on each side if possible. Plenty of ventilation is necessary, and all vent holes covered with screen should be thoroughly cleaned every week as they become clogged up with dirt and ash. If the lamp-house is closed up tight the heat inside will become intense and the inner condenser lens will surely break. Care must be taken to avoid direct currents of air striking the lens, as it will break when very hot. Some operators have their lamp-house 'built so that the entire lamp may be removed when setting and trimming the carbons. At present there is a lamphouse built with the lamps on wheels so that the lamp can be rolled out and adjusted. Much has been written about condenser lens breakage, but all agree that if the lens case or mount is large enough so that the lens may expand, the only remaining cause will be the unequal heating caused by the arc being too close to the lens, or the sudden contraction of the lens when cooling. For instance, in winter after you have been running the lamp for four or five hours and then shut off the current it is not a bad idea to cover up the lamp-house so that it will not cool off as rapidly as if left exposed. If you are in doubt as to whether you are using direct or alternationg current, put in a set of carbons and switch on the light. After it burns' for ten or fifteen minutes, if the arc is quiet — that is, it does not hum — you have direct current. If it continues to hum you have alternating current. Open the switch, and if one carbon remains heated longer than the other you have direct current, the one remaining hot longer is the positive one and should be placed on top. If both carbons cool off equally fast you have alternating current. The crater will form on the positive carbon when using direct current, while the negative one will burn to a point. For alternating current either lead wire may be attached to the upper carbon as it is alternately positive and -negative. Any queries regarding carbons and arc lamps will be promptly answered ; and operators are invited to send in their opinions and experiences as to the best methods of setting and regulating the carbons and arc lamps. BLUR IN THE PICTURE. We have a query from South Dakota in regard to blurring of the picture on the screen. The writer states that the ends of the picture can be brought out sharp by focusing the projection lens, but the center is blurred. He asks whether the fault is with the lens or the film track. Your trouble may be either with the lens or the film track. I would suggest that if possible you borrow a lens from a neighboring theater and try it out on your machine. If the picture is still at fault the trouble is with the film track. The film in passing across the aperture must lie in one plane'; if it bowls or cups, that is, the picture is not absolutely flat, you cannot get a sharp picture no matter how highgrade a lens you have. To test the film track lay a steel rule or any true surface on the tracks and you can easily see if the track is level. The film in passing over the track is pushed in and cups. Probably you will be able to file the tracks level ; if not you will require a new aperture plate. Concerning Motion Picture Reformers Under the caption "More Verdant Legislation," the editor of the Tampa (Fla.) Tribune says : "Representative Colson has introduced a bill in the Legislature to prohibit the exhibition of moving picture in Florida on Sunday. "Mr. Colson represents the county of Levy, which has a total population of 10,361 and the largest town of which .has a population of 864. The entire county has but a few more people than one ward of Tampa. Yet, Mr. Colson, basing his views of what is right and proper doubtless upon the customs and the opinions of his own county, seeks to legislate on the privileges and requirements of counties like Hillsborough, Duval and Escambia and cities like Tampa, Pensacola and Jacksonville. "From the viewpoint of Levy county, moving pictures on Sunday are probably wrong. We doubt if Levy ever had a moving picture exhibition within its borders. There is in Levy county with no large working class, people who are compelled, throughout the week, to devote their time to labor in shop, in office or in factory and who, therefore, have no leisure during the week for innocent diversion. To this large class, composing a great majority of the residents of cities like Tampa, the motion picture show on Sunday gives the opportunity at trifling cost, for entirely innocent and instructive amusement. We speak now of the strictly motion picture show — we are not ourselves in favor of vaudeville shows on Sunday, and would have no quarrel with Mr. Colson if his bill prohibited such exhibitions, really desecratory of the Sabbath day and not in the slightest degree elevating or helpful. But we earnestly dissent to a proposition which would deprive our . people of the harmless pleasure of a few minutes on Sundays in the motion picture house, where pictures of an instructive and never unclean sort are exhibited and, frequently, Biblical subjects are most impressively conveyed. "Mr. Colson is probably ignorant of just what a motion picture exhibition is and imagines that it is of the same stripe as the variety show or the cheap vaudeville production, which are permitted in some cities and which should be prohibited on Sunday. Some of his colleagues ought to conduct him to a first class motion picture theater, such as we have in Tampa, and make him acquainted with just what it is, challenging him to find a reasonable objection to its operation on Sunday or any other day."